Rheostat.



PATENTED APR. 11, 1905.

F. E. GOODALL.

RHBOSTAT;

APPLICATION FILED-00T- 6. 1904.

UNITED STATES Patented April 11, 1905.

PATENT OFFICE.

FRED E. GOODALL, OF CHICAGO, ILLINOIS, ASSIGNOR TO HANSON & VAN VVINKLE COMPANY, A CORPORATION OF NEIV JERSEY.

FlHEOSTAT.

SPECIFICATION forming part of Letters Patent No. 787,032, dated April 11, 1905.

Application filed October 6, 1904. Serial No. 227,464.

To (LZZ whom it may concern.-

Be it known that I, FRED E. CrooDALL, a citizen of the United States of America, and a resident of Chicago, county of Cook, and State of Illinois, have invented certain new and useful Improvements in Rheostats, of which the following is a specification.

My present invention relates to rheostats, and has for its object to provide a simple, compact, and efiicient rheostat and one in which parts of the same may be readily sepa rated for the purpose of removal, rearrangement, and replacing of the same. Such a device is fully, clearly, and exactly described in the following specification and shown in the accompanying drawings, in which like reference characters refer to like parts, and in wl1ich Figure 1 is a plan-view of a rheostat constructed in accordance with my invention; and Fig. 2 is a transverse section of the same on the line 2 2, Fig. 1.

Referring in detail to the drawings, A represents a base of non-conductive or insulating material, such as slate, and upon which are mounted binding-posts B and C.

D is a central post or pivot of conductive material electrically connected to post B in usual manner. (Not shown.) Post or pivot D has an annular shoulder D, upon which is mounted the switch or contact arm E, made of brass or other metal, preferably a spring metal. Switch or arm E is curved or bent upon itself, its two ends projecting out near together to form contact-points F and G, the springy nature of the material of which arm or switch E is made tending to hold said points F G apart. One end of arm or switch E is pivoted on post or pivot D and rotates on shoulder D. Secured or fixed to the other end of arm or switch E is an operating-arm II, provided with a handle I, by means of which the contact-points are shifted to change the resistance.

Mounted radially and circumferentiall y about post or pivot D on base A are contactblocks J and K of conductive material, such as brass, block K being dead and blocks J being connected electrically. The blocks J and K have contact points or lips O P, adapted to receive therebetween and embrace the contact ends F and Cr of the switch or arm E upon rotation of the arm H.

Contact-blocks J are connected electrically by resistance-coils L M of graduated diameters and mounted above blocks J on two circumferential lines. The ends of coils L are mounted adjacent the outer peripheries, Fig. 2, and on the far sides of adjacent blocks J in sockets J, Fig. 1, formed in a plane perpendicular to the plane of location of the blocks J. The ends of coils L are secured by screws N in the sockets J. The ends of coils M are mounted near the center and on the far sides of adjacent blocks J in sockets J being held in said sockets by screws N.

Set-screws N and N are respectively seated in horizontal radial screw-threaded perforations N and N on opposite sides of blocks J in line with sockets J and J, and hence lie horizontall y and extend radially with respect to the center of post or pivot D. As the sockets J and J 2 are formed perpendicular to the plane of location of the blocks J, coils L and M lie substantially. within the same vertical plane with blocks J, the coils L being at the outer ends of blocks J, and the coils M being at the inner ends of blocks J, and the sockets J and J in which the ends of coils L and M are mounted, being on opposite sides of blocks J, so that said' coils overlap each other.

In operation the handle I is grasped and rotated to bring the switch or arm E into contact first with the blocks J, upon which are mounted the coils L and M of greatest diameter, so that the power is gradually increased as the coils diminish in diameter. When not in use, the switch or arm E is in contact with block K, which is dead. The double elastic contact-points F Cr on switch or arm E being embraced by the contact points or lips O I serve to clean the surfaces of said contactpoints at every movement of the switch or arm E, and hence insures at all times good contact and protection against insulation by oil or other matter. The mounting of the coils L and M, as described, is simple and compact, which is adcsideratum, and, with the peripheral arrangement of screws N and N, making it possible to easily remove any one of the coils for the purpose of substituting therefor a new coil or a coil of greater or smaller diameter. By thus compactly mounting coils L and M the same are brought substantially Within the circumference of the contact-blocks, thus protecting the same from damage. Furthermore, the mounting of the ends of coils L and M in the far sides of adjacent blocks J and the overlapping of said coils permits of disposition of greater lengths of coils about the circumference of contactblocks.

Having thus described my invention, what I claim as new, and desire to secure byLetters Patent, is

1. A rheostat having an arm mounted to swing about a center and provided with two elastic contact points; with contact blocks disposed circumferentially about the center and provided with contact-points that embrace the contact-points of the arm, and resistance-coils mounted over the blocks and connecting the contact-blocks as described.

2. A rheostat having a switch-arm made of a curved piece of metal whereby its ends are near together and are held apart by the spring of the arm itself and mounted upon a center and adapted to swing about a center and its ends to engage contact-blocks disposed circumferentially about the center; said contactblocks connected together by resistance-coils and provided with contact-points that embrace the ends of the arm substantially as shown.

3. A rheostat having an arm mounted upon a center and adapted to revolve about the center and engage contact-blocks radially disposed about the center, the contact between the arm and the blocks made by one member embracing the other by elastic contact and resistance coils connecting the blocks and mounted above the blocks in two circumferential lines, substantially as shown.

I. A rheostat having a switch-arm mounted upon a center and adapted to swing around and engage contact-blocks radially disposed about the center and resistance-coils connecting the blocks mounted above the blocks and connecting-sockets for the coils in the blocks disposed perpendicular to the plane of location of the blocks; said arm made of a curved piece of metal having its two ends bent near together whereby each end acts as a contact-point and said contact-blocks provided with two contactpoints one for each point of the arm, substantially as shown.

5. A rheostat having a switch-arm mounted upon a center and adapted to be swung around and engage contact-blocks radially disposed above the center; said arm composed of a bent piece of metal having its two ends near together and said blocks provided with two contact-points one for each 01 the ends of the arm; resistance-coils disposed circumfercntially about the center and connecting the blocks, substantially as shown.

6. A rheostat having a switch-arm mounted upon a center and adapted to be revolved about the center and engaged in contact-blocks radially disposed about the center said blocks connected together by resistance-coils located circumferentially about the center, said blocks provided with contact-points adapted to cmbrace the contact-points of the arm and said arm provided with contact-points having an elastic pressure of contact, substantially as shown.

7. In a rheostat the combination with a rotating switch comprising electric contactpoints, of contact-blocks disposed about said switch having contact points or lips adapted to embrace the contact-points on said switch.

8. In a rheostat the combination with a 1'0- tating switch comprising a pair of contactpoints of spreading tendency, of contactblocks disposed about said switch and having contact points or lips adapted to embrace the contact-points on said switch.

9. In a rheostat the combination with a rotating switch, of contact-blocks disposed radially and cireum't'erentially about said switch and adapted to contact therewith, of resistance-coils connecting said contact-blocks and mounted in the same vertical plane therewith.

10. In a rheostat the combination with a rotating switch and contact-blocks radially and circumferentially disposed thereabout, of vertical sockets in said blocks and resistancecoils mounted in said sockets lying vertically above the blocks.

11. In a rheostat the combination with a rotating switch and contact-blocks radially and circumferentially disposed thereabout, of vertical sockets in said blocks, resistance-coils mounted in said sockets and set-screws circumferentiall y mounted in said blocks and impinging said coils.

12. In a rheostat, the combination with a rotary switch and contact-blocks disposed radially and circum't'erentially about the same, of resistance-coils connecting the blocks in pairs, respectively, and lying vertically over the bloc is connected and extending from outer side to outer side of the pair, and a second set of coils lying nearer the center of rotation and similarly connecting adjacent blocks of adjacent pairs.

13. In a rheostat the combination with a rotating switch and contact-blocks disposed radially and circumferentially thereabout, of overlapping resistance-coils seated in said blocks in two circumferential rows about said Signed at Chicago this 14th day of Septemswitch. 1 b 1 her, 1904.

14:. In a rheostat tie com ination Witi a rotating switch and contact-blocks disposed FRED GOODALL' 5 radially and circumferentially tlierealoout, of Witnesses:

resistance-coils seated in vertical sockets ad- CHAs. W. MARsHALL, jacent the outer periphery of the same. DAN \VILLIAMS. 

